Infrared spectra of the CH3Cl:NO complex isolated in solid neon have been investigated. Most of the vibrationalmodes of the complex have been detected. The weak interaction between NO and CH3Cl in CH3Cl:NO isresponsible for small shifts of the vibrational mode frequencies of both CH3Cl and NO molecules. The measuredshifts range between −3.2 and + 3.8 cm-1. On the basis of DFT calculations, different geometries have beenexplored for the complex, and it has been shown that the most stable structure is of C1 symmetry. The calculatedfrequency shifts match well the experimental data.